. >> reporter: until they followed the brown pelicans to mexico's sea of cortez. for every minute of the show, there are ten hours of film this didn't make air. >> i think anything that can fly that is mechanical, manmade, put a camera on it. but we also made miniature cameras birds could carry. >> reporter: four years in the making, they hand raised snow geese and a vulture to fly with cameras for this film. >> how did you get them to keep it on? >> we basically developed harnesses and the way it was so carefully positioned, it didn't disturb their flight. >> reporter: he also used spy cameras. it took more than 100 days of shooting to get this spectacular scene. using human ingentlem all its w. anne thompson, nbc news, new york. >> spectacular. that's our broadcast on a thursday night. thank you for being here with us and please don't forget "rock center" tonight at 10:00 eastern, 9:00 central. it includes the interview with mark zuckerberg. we hope to see you back here tomorrow evening. good night.